1e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===// 2e78f53d1SNikolas Klauser // 3e78f53d1SNikolas Klauser // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4e78f53d1SNikolas Klauser // See https://llvm.org/LICENSE.txt for license information. 5e78f53d1SNikolas Klauser // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6e78f53d1SNikolas Klauser // 7e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===// 8e78f53d1SNikolas Klauser 9*ce777190SNikolas Klauser #ifndef _LIBCPP___CXX03___COMPARE_THREE_WAY_COMPARABLE_H 10*ce777190SNikolas Klauser #define _LIBCPP___CXX03___COMPARE_THREE_WAY_COMPARABLE_H 11e78f53d1SNikolas Klauser 1273fbae83SNikolas Klauser #include <__cxx03/__compare/common_comparison_category.h> 1373fbae83SNikolas Klauser #include <__cxx03/__compare/ordering.h> 1473fbae83SNikolas Klauser #include <__cxx03/__concepts/common_reference_with.h> 1573fbae83SNikolas Klauser #include <__cxx03/__concepts/equality_comparable.h> 1673fbae83SNikolas Klauser #include <__cxx03/__concepts/same_as.h> 1773fbae83SNikolas Klauser #include <__cxx03/__concepts/totally_ordered.h> 1873fbae83SNikolas Klauser #include <__cxx03/__config> 1973fbae83SNikolas Klauser #include <__cxx03/__type_traits/common_reference.h> 2073fbae83SNikolas Klauser #include <__cxx03/__type_traits/make_const_lvalue_ref.h> 21e78f53d1SNikolas Klauser 22e78f53d1SNikolas Klauser #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 23e78f53d1SNikolas Klauser # pragma GCC system_header 24e78f53d1SNikolas Klauser #endif 25e78f53d1SNikolas Klauser 26e78f53d1SNikolas Klauser _LIBCPP_BEGIN_NAMESPACE_STD 27e78f53d1SNikolas Klauser 28e78f53d1SNikolas Klauser #if _LIBCPP_STD_VER >= 20 29e78f53d1SNikolas Klauser 30e78f53d1SNikolas Klauser template <class _Tp, class _Cat> 31e78f53d1SNikolas Klauser concept __compares_as = same_as<common_comparison_category_t<_Tp, _Cat>, _Cat>; 32e78f53d1SNikolas Klauser 33e78f53d1SNikolas Klauser template <class _Tp, class _Cat = partial_ordering> 34e78f53d1SNikolas Klauser concept three_way_comparable = 35e78f53d1SNikolas Klauser __weakly_equality_comparable_with<_Tp, _Tp> && __partially_ordered_with<_Tp, _Tp> && 36e78f53d1SNikolas Klauser requires(__make_const_lvalue_ref<_Tp> __a, __make_const_lvalue_ref<_Tp> __b) { 37e78f53d1SNikolas Klauser { __a <=> __b } -> __compares_as<_Cat>; 38e78f53d1SNikolas Klauser }; 39e78f53d1SNikolas Klauser 40e78f53d1SNikolas Klauser template <class _Tp, class _Up, class _Cat = partial_ordering> 41e78f53d1SNikolas Klauser concept three_way_comparable_with = 42e78f53d1SNikolas Klauser three_way_comparable<_Tp, _Cat> && three_way_comparable<_Up, _Cat> && 43e78f53d1SNikolas Klauser common_reference_with<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>> && 44e78f53d1SNikolas Klauser three_way_comparable<common_reference_t<__make_const_lvalue_ref<_Tp>, __make_const_lvalue_ref<_Up>>, _Cat> && 45e78f53d1SNikolas Klauser __weakly_equality_comparable_with<_Tp, _Up> && __partially_ordered_with<_Tp, _Up> && 46e78f53d1SNikolas Klauser requires(__make_const_lvalue_ref<_Tp> __t, __make_const_lvalue_ref<_Up> __u) { 47e78f53d1SNikolas Klauser { __t <=> __u } -> __compares_as<_Cat>; 48e78f53d1SNikolas Klauser { __u <=> __t } -> __compares_as<_Cat>; 49e78f53d1SNikolas Klauser }; 50e78f53d1SNikolas Klauser 51e78f53d1SNikolas Klauser #endif // _LIBCPP_STD_VER >= 20 52e78f53d1SNikolas Klauser 53e78f53d1SNikolas Klauser _LIBCPP_END_NAMESPACE_STD 54e78f53d1SNikolas Klauser 55*ce777190SNikolas Klauser #endif // _LIBCPP___CXX03___COMPARE_THREE_WAY_COMPARABLE_H 56